Along with the continuous development of organic electro-luminescence (OLED) technology, as well as continuous evolution of OLED devices, packaging method and packaging level of OLED device have always been the key topics discussed in the industry.
Since water and oxygen are natural enemies of organic materials, they can not only break an unsaturated bond of a polymer to accelerate aging of an organic material, but also cause damage to electrodes in a device. The packaging level of an OLED device determines both lifespan and environmental dependence of the device.
UV glue packaging is a common packaging method of an OLED device in laboratories, and has low cost and simple operations, but UV glue may contact the device during UV curing, producing a bad influence on the device, making the device fail to be applied to the actual industry. Frit packaging is a packaging method that uses glass powder for curing so that a packaging glass and a substrate bond together, and is a comparatively mature packaging method in the industry. A disadvantage of this method is that curing effect of glass powder cannot be controlled, and a crack may occur during the glass powder curing, which may affect packaging effect, and air may enter the device through the crack, affecting lifespan of the device. In view of the disadvantage of Frit packaging, thin film packaging, in which an OLED device is packaged by preparing an organic-inorganic alternating multilayer thin film on a surface of the cathode of the OLED device, starts to show its advantage, but packaging process of this method is too complicated and immature and has low productivity.